How do you get your drinking water? A great article by our friend, Zhai Yun Tan

Before you take a gulp of water, try to mentally trace where that water that just gushed out of your taps has been: How did it go from that weird-tasting raindrop to the clear, odorless water that is sitting in your glass now?

Safe drinking water is a privilege Americans often take for granted — until a health crisis like the one in Flint, Mich., happens that makes us think about where it comes from and how we get it.

Our drinking water comes from lakes, rivers and groundwater. For most Americans, the water then flows from intake points to a treatment plant, a storage tank, and then to our houses through various pipe systems.

Various other chemicals can be added to adjust for hardness and pH levels or to prevent corrosion, based on the water source. But depending on where you are in the United States, there can be different challenges, and corresponding methods of treating drinking water. For example:

(Top) Older pipes can be treated with a chemical to prevent corrosion and contamination of the water supply. (Bottom) When Flint, Mich., changed its water source, it didn’t treat the water to prevent corrosion of the pipes, which contributed to high lead levels in the water.

Annette Elizabeth Allen for NPR

Lead pipes or fittings are a culprit in the current water crises in Flint, Baltimore and other cities. Many old water pipes are made of lead, which may leach into the water supply if preventive measures aren’t taken. According to EPA, even low levels of lead can cause behavior problems, slow growth and affect IQ levels.

While the most effective solution might be to replace lead pipes entirely, water utilities usually add some form of phosphate to the water supply. That forms a protective film between the lead pipe and the water flowing through it.

Flint failed to add orthophosphate to control corrosion when it switched water sources from the city of Detroit to the Flint River; water from the Flint River has eight times more chloride than Detroit’s, which is highly corrosive to the pipe.

Agricultural States May Suffer From High Levels Of Nitrate

Enlarge this image

In farming communities across the country, water can be contaminated by fertilizer and livestock.

Annette Elizabeth Allen for NPR

Nitrate runoff in rivers and groundwater can be common in places with high levels of farming activities. Fertilizers, manure storage and septic systems are sources of this pollution. High levels of nitrate in drinking water can cause “blue-baby syndrome,” where infants younger than 6 months suffer from shortness of breath. If untreated, it might lead to death.

Water with high salinity is prevalent in the western part of the United States. In some places, the water can be too salty for drinking or other uses and needs to undergo desalination. These saline water sources include seawater and brackish groundwater.

Turning seawater into drinking water is a relatively new concept. The Carlsbad plant in California that opened last year is the largest seawater desalination plant, and some see it as a possible solution to the statewide drought.

Brackish groundwater has high levels of salt but not as much as seawater. Texas relies heavily on brackish groundwater as a water source.

Most of it was Legionellosis, a disease typically spread by water droplets in the air. The remaining cases were associated with bacteria and viruses that can be killed by chlorine. To prevent such outbreaks, CDC emphasized the importance of ensuring a sufficient level of disinfectant, such as chlorine, is present in the water from the time it leaves the treatment center to when it arrives in our pipes.

Some utilities use ozone as a disinfectant to kill bacteria and viruses, a method some say is more effective than the usual route of using chlorine. Ozone is bubbled into the water in huge tanks, destroying illness-causing microorganisms. It also gets rid of taste and odor in the water.

Watersheds are the areas where rivers, lakes and ponds drain into, and they’re a source of drinking water. Some cities, such as Seattle and New York, are famous for the regulations and programs they put in place to protect their watersheds.

New York City gets its water from multiple watersheds that are well-protected. The quality of the water is so good that it does not need to undergo filtration at the treatment plants.

The city works with farmers and landowners upstream to reduce pollution and manage land. The Conservation Easement Program sells or donates land to conservation organizations, limiting the type of development that can occur on it permanently.

From the lake to the tap, water goes through many steps to become safe for us to drink. It is a crucial process that requires constant monitoring, and — as both history and current events show — it’s one that can be easily threatened by bacterial outbreaks, natural disasters and human activity.

Before you take a gulp of water, try to mentally trace where that water that just gushed out of your taps has been: How did it go from that weird-tasting raindrop to the clear, odorless water that is sitting in your glass now?

Safe drinking water is a privilege Americans often take for granted — until a health crisis like the one in Flint, Mich., happens that makes us think about where it comes from and how we get it.

Our drinking water comes from lakes, rivers and groundwater. For most Americans, the water then flows from intake points to a treatment plant, a storage tank, and then to our houses through various pipe systems.

Various other chemicals can be added to adjust for hardness and pH levels or to prevent corrosion, based on the water source. But depending on where you are in the United States, there can be different challenges, and corresponding methods of treating drinking water. For example:

(Top) Older pipes can be treated with a chemical to prevent corrosion and contamination of the water supply. (Bottom) When Flint, Mich., changed its water source, it didn’t treat the water to prevent corrosion of the pipes, which contributed to high lead levels in the water.

Annette Elizabeth Allen for NPR

Lead pipes or fittings are a culprit in the current water crises in Flint, Baltimore and other cities. Many old water pipes are made of lead, which may leach into the water supply if preventive measures aren’t taken. According to EPA, even low levels of lead can cause behavior problems, slow growth and affect IQ levels.

While the most effective solution might be to replace lead pipes entirely, water utilities usually add some form of phosphate to the water supply. That forms a protective film between the lead pipe and the water flowing through it.

Flint failed to add orthophosphate to control corrosion when it switched water sources from the city of Detroit to the Flint River; water from the Flint River has eight times more chloride than Detroit’s, which is highly corrosive to the pipe.

Agricultural States May Suffer From High Levels Of Nitrate

Enlarge this image

In farming communities across the country, water can be contaminated by fertilizer and livestock.

Annette Elizabeth Allen for NPR

Nitrate runoff in rivers and groundwater can be common in places with high levels of farming activities. Fertilizers, manure storage and septic systems are sources of this pollution. High levels of nitrate in drinking water can cause “blue-baby syndrome,” where infants younger than 6 months suffer from shortness of breath. If untreated, it might lead to death.

Water with high salinity is prevalent in the western part of the United States. In some places, the water can be too salty for drinking or other uses and needs to undergo desalination. These saline water sources include seawater and brackish groundwater.

Turning seawater into drinking water is a relatively new concept. The Carlsbad plant in California that opened last year is the largest seawater desalination plant, and some see it as a possible solution to the statewide drought.

Brackish groundwater has high levels of salt but not as much as seawater. Texas relies heavily on brackish groundwater as a water source.

Most of it was Legionellosis, a disease typically spread by water droplets in the air. The remaining cases were associated with bacteria and viruses that can be killed by chlorine. To prevent such outbreaks, CDC emphasized the importance of ensuring a sufficient level of disinfectant, such as chlorine, is present in the water from the time it leaves the treatment center to when it arrives in our pipes.

Some utilities use ozone as a disinfectant to kill bacteria and viruses, a method some say is more effective than the usual route of using chlorine. Ozone is bubbled into the water in huge tanks, destroying illness-causing microorganisms. It also gets rid of taste and odor in the water.

Watersheds are the areas where rivers, lakes and ponds drain into, and they’re a source of drinking water. Some cities, such as Seattle and New York, are famous for the regulations and programs they put in place to protect their watersheds.

New York City gets its water from multiple watersheds that are well-protected. The quality of the water is so good that it does not need to undergo filtration at the treatment plants.

The city works with farmers and landowners upstream to reduce pollution and manage land. The Conservation Easement Program sells or donates land to conservation organizations, limiting the type of development that can occur on it permanently.

From the lake to the tap, water goes through many steps to become safe for us to drink. It is a crucial process that requires constant monitoring, and — as both history and current events show — it’s one that can be easily threatened by bacterial outbreaks, natural disasters and human activity.

Before you take a gulp of water, try to mentally trace where that water that just gushed out of your taps has been: How did it go from that weird-tasting raindrop to the clear, odorless water that is sitting in your glass now?

Safe drinking water is a privilege Americans often take for granted — until a health crisis like the one in Flint, Mich., happens that makes us think about where it comes from and how we get it.

Our drinking water comes from lakes, rivers and groundwater. For most Americans, the water then flows from intake points to a treatment plant, a storage tank, and then to our houses through various pipe systems.

Various other chemicals can be added to adjust for hardness and pH levels or to prevent corrosion, based on the water source. But depending on where you are in the United States, there can be different challenges, and corresponding methods of treating drinking water. For example:

(Top) Older pipes can be treated with a chemical to prevent corrosion and contamination of the water supply. (Bottom) When Flint, Mich., changed its water source, it didn’t treat the water to prevent corrosion of the pipes, which contributed to high lead levels in the water.

Annette Elizabeth Allen for NPR

Lead pipes or fittings are a culprit in the current water crises in Flint, Baltimore and other cities. Many old water pipes are made of lead, which may leach into the water supply if preventive measures aren’t taken. According to EPA, even low levels of lead can cause behavior problems, slow growth and affect IQ levels.

While the most effective solution might be to replace lead pipes entirely, water utilities usually add some form of phosphate to the water supply. That forms a protective film between the lead pipe and the water flowing through it.

Flint failed to add orthophosphate to control corrosion when it switched water sources from the city of Detroit to the Flint River; water from the Flint River has eight times more chloride than Detroit’s, which is highly corrosive to the pipe.

Agricultural States May Suffer From High Levels Of Nitrate

Enlarge this image

In farming communities across the country, water can be contaminated by fertilizer and livestock.

Annette Elizabeth Allen for NPR

Nitrate runoff in rivers and groundwater can be common in places with high levels of farming activities. Fertilizers, manure storage and septic systems are sources of this pollution. High levels of nitrate in drinking water can cause “blue-baby syndrome,” where infants younger than 6 months suffer from shortness of breath. If untreated, it might lead to death.

Water with high salinity is prevalent in the western part of the United States. In some places, the water can be too salty for drinking or other uses and needs to undergo desalination. These saline water sources include seawater and brackish groundwater.

Turning seawater into drinking water is a relatively new concept. The Carlsbad plant in California that opened last year is the largest seawater desalination plant, and some see it as a possible solution to the statewide drought.

Brackish groundwater has high levels of salt but not as much as seawater. Texas relies heavily on brackish groundwater as a water source.

Most of it was Legionellosis, a disease typically spread by water droplets in the air. The remaining cases were associated with bacteria and viruses that can be killed by chlorine. To prevent such outbreaks, CDC emphasized the importance of ensuring a sufficient level of disinfectant, such as chlorine, is present in the water from the time it leaves the treatment center to when it arrives in our pipes.

Some utilities use ozone as a disinfectant to kill bacteria and viruses, a method some say is more effective than the usual route of using chlorine. Ozone is bubbled into the water in huge tanks, destroying illness-causing microorganisms. It also gets rid of taste and odor in the water.

Watersheds are the areas where rivers, lakes and ponds drain into, and they’re a source of drinking water. Some cities, such as Seattle and New York, are famous for the regulations and programs they put in place to protect their watersheds.

New York City gets its water from multiple watersheds that are well-protected. The quality of the water is so good that it does not need to undergo filtration at the treatment plants.

The city works with farmers and landowners upstream to reduce pollution and manage land. The Conservation Easement Program sells or donates land to conservation organizations, limiting the type of development that can occur on it permanently.

From the lake to the tap, water goes through many steps to become safe for us to drink. It is a crucial process that requires constant monitoring, and — as both history and current events show — it’s one that can be easily threatened by bacterial outbreaks, natural disasters and human activity.